Buttonhole sewing machine



Dec- 12, 1933- H. c. MILLER 1,939,271

BUTTONHOLE SEWING MACHINE Filed April 25, 1951 9 Sheets-Sheet l Defn 12,1933. H. c. MILLER 1,939,271

BUTTONHOLE SEWING MACHINE Filed April 25, 1931 9 Sheets-Sheet 2 XecafarsDec. l2, 1933. H C. MlLLER 1,939,271

BUTTONHOLE SEWING MACHINE Filed April 25, 1931 9 Sheets-Shel??l 3 i LZ79.1 I 2 Dec. 12, 1933. H Q MULLER 1,939,271

BUTTONHOLE SEWING MACHINE Filed April 25, 1931 9 Sheets-Sheet 4 nIl DCC.12, 1933. CF MILLER BUTTONHOLE SEWING MACHINE Filed April 25. 1931 9Sheets-Sheet 5 Dec. 12, 1933. f H, C, MER 1,939,271

BUTTONHOLE S EWING MACHINE Filed April 25, 1931 9 SheeLS-Sheet 6BUTTONHOLE SEWING MACHINE Filed April 25, 1931 9 Sheets-Sheet '7 :551, 6mfw@ btozmq Dec. 12, 1933. H, c. MILLER 1,939,271

BUTTONHOLE SEWING MACHINE Filed April 25, 1931 9 Sheets-Sheet 8grt/vento@ Dec. 12, 1933. H..c. MILLER BUTTONHOLE SEWING MACHINE FiledApril 25, 1931 9 Sheets-Sheet 9 Patented Dec. 12, 1933 UNITED STATESYyPATENT OFFICE 1,939,271 BUTToNHoLE SEWING MACHINE Application April`25,1931. Serial No. 532,914

' 5 claims. (c1. i12- 73) This invention relates to improvements inbuttonhole sewing machines.

One of the obj ects of the invention is to improve Y the constructionshown in several prior patents issued to Henry C. Miller, whereby tomaterially increase the speed and accuracy of the operation of themachine.

A further object of the invention is to provide specific means forcontrolling the cloth clamp to l0 insure of the work being held inposition topre-l vent its removal, unless and until the stitches areproperly formed and the cutting blade has operated and returned tonormal position.

A further object of the invention is to provide specific improvements inthe thread control means, so that incase the stitches are improperlyformed or if the thread breaks or gives out, the cloth clamp cannot beraised to remove the work until the thread diiliculty has been cured andthe Work stitched over to thus avoid producing what is recognized in thetrade as seconds.

Another object of. the invention is to provide improved means forholding and severing the upper and lower threads.

A still further object of the invention is to provide means for layingin the short cut end of the upper or needle thread to be subsequentlyworked over and held in by the last barring stitches.

The invention also relates to improvements in the specific details ofconstruction and arrangement of the various devices designed tointerlock the parts between certain operations to insure of themechanism operating in a complete cycle to produce uniformand properlyformed buttonholes.

The invention also aims to provide improven ments in the means employedto control the operation of a complete cycle of movement of interrelatedparts by the stop motion device.

A further object of the invention is to provide improved means forinsuring operation of the buttonhole cutting blade and its completewithdrawal to normal position before the cloth clamp can be raised toremove the Work or the operator can again start the stitching mechanism.

Another object of the invention isto provide improved means forvibrating the gate carrying the needle bar, and means associatedtherewith for limiting or determining the lateral movement of the needlebar to insure uniformity of stitches.

A further object of the invention is to provide means for locking thebelt shifting means during that part of the cycle of movement necessaryin forming a buttonhole when power is applied to the fast pulley,to'prevent an operatorcarelessly or inadvertently disrupting themechanism While the power is directly applied.

A still further object of the invention is to provide improved means forforming part of the stitches; operating the cutting blade; and throwing,or permitting the throwing out, of certain latches by momentum of themachine after disconnection of the power and release of the stop motiondevice.

An important object of the invention is to provide improved treadlemechanism whereby an operator simply moves a treadle back and forth toactuate the machine, and in case various latches have locked certaindevices, due to improper stitching or failure of the stop motion orcutting blade returning to normal position, althoughv the treadle may beidled, the machine cannot again be started until the diiculty has beencured.

Another object of the invention is to provide improvements in the meansemployed to control and actuate the various locking and interlockingmechanisms through, and more or less by, the starting lever.

The invention also relates to improvements in the details ofconstruction and arrangement of 30 parts as will be hereinafterdescribed and particularly pointed out in the claims.

In the drawings:

Fig. 1 is a perspective view of a buttonhole sewing machine showing theapplication of th improvements.

Fig. 2 is a front elevation of the buttonhole sewing machine.

Fig. 3 is an end View.

Fig. 4 is a view from the opposite end.

Fig. 5 is a bottom plan View.

Fig. 6 is a detail perspective view of the belt shifting lever andassociated parts, and the stop motion lock.

Fig. 7 is a detail view of the connections associated with the stopmotion device for operating the cutting blade.

Fig. 8 is a detail plan view of the connection for operating the upperthread holding and cutting mechanism.

Fig. 9 is a detail perspective view of the same.

Figs. 10 and 10a are detail perspective views of the cloth clamp and theconnections mounted thereon.

- Fig. 11 is a detail plan view of the presser foot.

Fig. 12 is a detail horizontal section of the same on the line 12-12 ofFig. 13.

Fig. 13 is a detail transverse section on the line 13-13 ofV Fig. 11,the parts being shown somewhat enlarged to illustrate the parts.

CII

Fig. 14 is a detailV top plan view of the lower thread holding andcutting mechanism showing the parts in full line position after havingoperated to cut and hold the thread, and also ,showing in dotted linesthe movementsl of the lever and platel Fig. is a detail perspective viewof the same but showing the parts in open position to receiveV varioustension devices and the course of the upper thread from the source ofsupply to the needle.

Fig. 18 isa detail view of the connection for operating the upper threadslackening device.

Fig. 19 is a detail section of one of the tensioning devices.

Fig. is a section of same on the line 20-20 of Fig. 19. v l

Fig. 21 is a similar view taken on the line 21-21 of Fig. 19.

Fig. 22 is a detail perspective view of the cutting blade interponentand associated parts.

Fig.` 23 is a detail plan view of the gate operating mechanism.

Fig. 24 is a detail perspective view of the treadle mechanism, showingthe parts in neutral or normal position.

Y Fig. vis a detail elevation of the treadle mechanism showing the partsin full lines in one extreme position, and in dotted lines 1n its otherextreme position. l

Fig. 26 is a detail in elevation of the starting lever, showing itsnormal position in full lines, and its operative position tov raise thecloth clamp in dotted lines.

To illustrate the invention, the improvements are shown and describedVin connection with a well known type of Singer buttonhole machine.Therefore, it will be necessary to refer in a general way' to certainwell recognized features in this type of machine, to fully understandand comprehend lthe construction and operation of the improvements aboutto be described.

1 indicates the base, 2 the arm or head, 3 the power shaft, 4 the needlebar, 5 a cam shaft carrying the usual cam disc operatively connectedwith the power shaft, 6 the stop motion device, and 7 the cloth clamp.The essential features of the stop motion device are substantially thesame as that disclosed in the patent to Miller, No. 1,438,848 datedrDecember 12, 1922, but the connections associated therewith have beenmaterially changed to perform new functions, as will later appear.

Mounted on the base 1 is a shaft 8, on which is supported a startinglever 9 having an extension 11. On the inside of the starting lever ,9is a roller 10 which cooperates with the cloth clamp 7 to raise thelatter. The free end of the extension 11 lies overa roller 12 on a ybeltshifting lever 13 mounted on a stud 14 and positioned to engage, but notconnected with, the upper end of the stop motionvdevice 6.

Extending from the opposite side of the stop motion device is an arm 15,to which is pivoted a rod 16, provided with a notch 17, Fig. 3.

The cloth clamp 7 is of conventional type and is pivoted at 19 on theusual step by step feeding mechanism, and is held in operative positionby a spring 20, mounted on a rod 21 slidably and foot, is a horizontalrecess 25.

tiltably supported at its upper end in a bearing v22 on the body of themachine; the lower end of the rod being tiltably supported on the top ofthe clamp and moving therewith. 1t is to be noted that the rod carryingthe spring 20 does not extend through the clamp to the base, so that thespace to receive the cloth extends back as far as the clamp mounting.Thus, the cloth can be operated upon a greater distance from the edgethereof than is possible when the rod is mounted on the base. Theforward end of the cloth clamp has secured to it the usual presser foot23 to engage the cloth. On one end of the presser foot 23 is anextension 24 and under the same, and in the end of the presser Mountedon a shaft 26 mounted in the extension 24 are two substantiallyhook-shaped blades 27 and 28, one 27 serving to pull the upper threadinto the recess 25, and the other 28 serving as a knife to sever thethread, the blades cooperating respectively with the upper and lowerlwalls of the recess 25. The cutting edge 29 of the blade 28 is set backfrom the edge of the blade 27 so that when the blades are turned intothe recess, the upper blade 27 will first engage the thread and draw itin and pinch it against the Wall of the recess, and subsequently thecutting blade will act to sever the thread. 0n the upper end of theshaft 26 is an arm 3D, to which is pivoted the forward end of a rod 31,the opposite end of the latter being slidably mounted in. a bracket 31aextending from the cloth clamp. The bracket is formed with a slot 31bthrough which the rod 31 passed to support its end to permit lateralmovement, and a spring 31C holds the rod up against one wall of the slotand in operative position. y

On the inside of the starting lever 9 is a roller 32 which cooperateswith a cam 33 on the end of a lever 34, pivoted at35, on an extension ofthe cloth clamp 7, the rollers 10 and'32 being so positioned that in theoperation of lever 9, roller 32 will first Contact with cam 33 andthereafter the roller 10 will engage the rearwardly projecting tail ofthe cloth-clamp 7 to open the cloth-clamp. The lever34 is held in normaloperative position against a stop pin by a spring 34X, and the oppositeend of said lever is bevelled at 36 to cooperate with a bevelled lug 37adjustably mounted on the rod 3l, the lug 37 being retained in lateralcooperative position to be engaged by the bevelled end 36 of the lever34 by the spring 31C. A spring 38 is attached at one end to the rod 31,land at its oppo te end to the bracket 312L and serves to longitudinallyand normally pull a stop 3.9 on the rod 'J1 up against the bracket, andthus hold the blades 27 and 28 in one end of the recess 25 out of thepath of the needle as shown in Fig. 12.

Slidably mounted on the cloth clamp 7 an arm 40, which is bent down tobear on the upper surface of the clamp, Where it is conned byA a guide41. One'free end of this arm is bent downwardly and laterally andterminates at 42 epposite the end of the presser foot. Attached to theend of the arm is the bent end of a thread ejector 43. The ejector isAin the form of a right angle member, the horizontal portion 44 thereofextending between the end of the presser foot and the base, with its endnotched, as shown at 45, to engage the end of the previously severedupper thread, as will be hereinafter explained.

The rear end of the arm 40 is bifurcated, and

onithe bifurcated portion is mounted a plate 46,

provided with a slot 47, the plate being adjustably secured in place bya set screw 48. The rear end of this plate contacts with a shaft 49,Figs. 1 and 2, to limit the movement of the ejector 43 to properlyposition it out of the path of the needle when the parts'are at rest. Aspring 50 is secured at one end to the arm 40 and its opposite end isfastened to a pin extendingrfrom the cloth clamp. The tension of thisspring is such as to draw the arm toward the shaft 49 to normallyposition the ejector. The arm 40 is formed with a shoulder 5()a normallyspaced from the rod 21 when the plate 46 contacts with shaft 49. In thebeginning of the stitching operation, the clamp Aadvances until the rod2l contacts with the shoulder 50e, and then both arm and clamp movetogether as will be explained.

The shaft 49 extendsl below the base and is provided with an arm 52,Fig. 5, in the path of cams 53, which extend from the usualcam disc onthe shaft 5. The upper end of the shaft 49 carries an arm 54,'which isconnected with the gate `operating mechanism in the top of the head. 1

One of the fundamental purposes of this invention is to so improve themechanismas will permit greatly increased speed. As a means toward thisend, the gate operating mechanismhas been materially improved byeliminating a nurnber of parts and arranging the construction in a wayto accurately andi definitely -throw the needle bar to exactpredetermined positions. to insure of uniformity and properly formedpurl and barring stitches. This mechanism consists of a stub shaftmounted in the top of the head ofthe machine, and geared to the powershaft is the usual cam disc 56, provided with a cam groove 57. Pivotedat 58 is a substantially L-shaped lever 59 provided at one end with aVroller 60, which engages in the cam groove 57, while the opposite arm ofthe lever is formed with a curved slot 61. 62 indicates a lever pivotedatV 63 to the usual connection 64 leading to the gate. This lever isprovided with a notch 64a in which seats a pin 65 extending'frorn thelever 59, a

spring 66 serving to normally hold the pin seated in the notch. On oneside of lever 62 is formed a cam 62X, Figs. 19 and 23, to operate atension device to be hereinafter referred to. A pin 67 extends from thelever 62 and fits in the slot 61 to guide said lever in its movementover the lever 59 and to retain the relationship between said levers topermit the desired motion from the cams. A link 67a connects the arm 54with the free end of the lever G2 to transmit motion from the cams 53 toshift the gate to form the end barring stitches.

Because of the rapidity of movement of the gate and the simplicity ofthe mechanism employed for operating the same, it is highly importantthat means be provided for insuring of the gateuniformly stopping at theend of its throw to avoid overthrow of the needle bar and consequentoverlashing of the stitches. This is accomplished by providing a stiffspring70 Afastened to one side of the end of the head. 71 indicates alink formed at one end with an eye to snugly nt around the bar 72 of thegate, while the opposite end of the link is threaded and passes throughan opening inthe upper end of the spring 70. The link 71 is clamped tothe spring by nuts 73 so as to permit ready adjustment between thespring and the gate to insure uniformity of throw to the needle bar. Y

`The spring 70 is without tension when the gate.

needle bar is in the center of the buttonhcle, hence when the gate isoscillated to one side or the other of the end barring stitches, thetension of the spring is increased toward the end of the throw, whichassists in limiting the movement ofthe gate under the action of theoperating cams, and at the same time this tension tends to return theneedle bar in the opposite direction.

Spring 70 is rather stiff, for obviously the flexibility of the partsbetween the gate and its op- `j erating means is quite susceptible ofpermitting overthrow of the needle bar. It is to cure this defect andinsure of the needle bar being limited in the throw in its rapidvibration, the stiff spring has been located to act directly on the Thismeans to prevent overthrow of stitches in a high speed machine has beenfound to be effective and reduces to a minimum the liability of thesitches overlapping the line of cut of the cutting blade.

The-lower stitch forming mechanism 73 is of the known Singer type andonly parts are conventionally illustrated for the purpose of showing itsrelation to lower thread holding and severing means. Fitted close to theunder surface of the base l, is a substantially U-shaped lever 74pivoted to the base at 75. The lever 74 is provided with a finger 76located to swing adjacent the path of the lower thread.

The U-shaped lever 74 is provided with a slot 77 to receive the end of aresilient connecting rod 78 held by a guide 79 and having its oppositeend adju-stably fixed to the under side of the base at 80. A lever 8l ispivoted at 82 to the underside of the base, and one end of this leverengages the resilient connecting rod 78, while the opposite end isprovided with an adjustable cam 83 to be engaged by the cams 53 on thecam disc mounted on the shaft 5. A spring 84 is connected between thelever 81 and the resilient connecting rod 78 to retain the cam 83 inposition to be engaged by the cams 53.

Pivoted at 75, below the U-shaped lever 74, is a swinging plate 85, fromone edge of which projects a combined thread puller and cutter j nectingrod 99, located under the base, and piv otally connected to an extensionon the end of the swinging plate 85 so that upon operation of the lever87, the blade 85a will move in an arc toward and away from the finger76. A spring 91 tends to draw the blade to its normal position "f andout of the way of the lower thread in the stitching operation. K

95 indicates a bracket fastened to one side of the body of the machine,and in a bearing formed in this bracket and a bearing formed in the basel, is a shaft 96. On the lower end of the shaft 96 is secured a camlever 97, held in normal operative position by a spring 98. Qn the upperend of the shaft 96 is adjustably mounted a stop 101 which cooperateswith a latch 162, ad-

justably mounted on a link 103, pivoted to the belt shifting lever 13.Aspring 104 secured to the head engages the inner surface of the linkand normally tends to press the latch 102 toward the stop 101.

lso

The rear end of the bracket is provided with a stop 105, againstv whichthe` lever 13 abuts when returned to normal position, a spring 106serving to draw the lever against the stop when released by the latch102.

On the shaft 5 ismcunted a gear wheel 107 and mounted on the face ofthis gear wheel, by a pivot 109, is a cam lever y108, the cam being heldin normal operative position against a stop pin 110 by a light spring111. The free end of the lever 97 isxin the path of the cam 108, and ineach revolution of the gear wheel, the cam contacts with said lever androcks the shaft 96 to release the latch k102 from the stop 101.

112 indicates a lever pivoted to the base at 113. The free end of thislever is curved to form a cam end 114, which is engaged by the pivot 109in the rotation of the gear wheel 107. Pivoted to the lever 112' at 115is a link 116, the opposite end of whichv is pivotally connected to alatch lever 117, pivoted on the under side of the base and held inoperative relation against the rod 16, by a spring 118, and is adaptedto engage the notch 17 to lock the stop motion device during a cycle ofoperationvin forming a buttonhole.

The lever 87 which imparts motion to the cutting blade is pivoted to theside-of the sewing machine head, and is operated by the stop motiondevice in the usual manner. One Vend of lever 87 is connected by a link120 through the medium of a pin 121 to a lever 122 pivoted to the headand extended into the end portion of same and connected to the bar towhich the usual cutting blade 88 is attached. The link 129 is slotted topermit movement on the pivot pin 121, and pivoted to the link is aT-shaped interponent 123, one leg of which is notched to engage underthe pin 121, while the other leg 124 cooperates .with a latch about tobe dee scribed. A spring 120,a attached to the interponent and a pin onthe head servesrto normally position the interponent so that the notchedend will be in position to engage the pin when the lever 87 is actuated.

A rod 125 is pivoted to the head and extends towards the opposite end ofthe machine and is bent down to engage in a cam slot 126 formed in adisc mounted on the shaft5. Secured to the rod 125 is a block 127 andattached thereto is a rod or latch 128, bent at its free end to lieunder the leg 124 of the interponent 123. Also secured to the block 127is a rod .129 which extends up above the top of the head and is bentdownwardly at 130 to cooperate with a thread tension and control device.l

Mounted in bearings on one side of the machine is shaft 131, andattached to one end thereof ana-rm 132 under control of thev stop motiondevice, rocked in one direction by a spring 132a and in the oppositedirection by the spring actuated rod 132b of said stop` motion device.Secured to the shaft 131 is a latch 133, the lower end of which isadapted to lie over the rear extension 11 of the starting lever 9. Alsofreely mounted on the shaft 131, is a hub 135 to which is attached adepending latch 136 also adapted 'to lie over the starting lever 9. Tothe hub is secured a trip lever 137 which extendstransversely acrossthe'machine and is retained in position by a light spring 1379, Fig. 22.One end of this lever overlies the starting rlever 9 and is adapted tobe engaged at one end by a resilient or cushion-like Wire member 138,supported von said starting lever, while the opposite end of lever'137is bentupwardly and shaped tov form a hook-like latch 139, Fig. 2. Thislatch, when in one position, is adapted to be engaged by a roller 140,Fig. 7, supported on the pivot pin 121.

In bearings on top of the machine head is mounted a shaft 141 extendedto form a crank arm 142. To the lower end of the crank arm 142, ispivoted a link 143 pivoted to the upper end of a reciprocatingconnection in the head which is operated by the usual power operatingmechanism. On a lug secured on the shaft 141, is fastened a thread guide144, the free end of which is bent over to form an eye 145 for thepassage of the needle thread. Extending from one end'of the shaft 141 isa lug 146, on which rests the down turned end 147 of a plate 148 hingedat 149 to a lug on the head. Below this plate is a thread tensioning.device 150, and a screw 151, passing through the plate, tension device,and lug, provides a means for adjusting the tension on the thread.

Rising from the top of the head is a standard on which is mounted athread tension device 152. The standard is provided with an opening 153to forma guide for the thread coming from a source of supply, Y y

Interposed between the standard and the plate 148, is a tension device154, and adjacent the hinge of the plate is another tension device 155.

Thetension device 155, while maintaining normal tension on the threadwhen the purl stitches are formed, releases the tension at the time thebar stitches are being placed. It comprises two discs 155a and 155i),between which the thread passes, the upper disc 155a having anopeningintercepted by a central bar 155c to t in a slot 155d in a post 155W.The tension is regulated by a spring and nut 155e, while a pin 155ffitted in the post is actuated by the cam 62X on the lever 62, when theend bars are formed, to release the tension on the thread. The lower endof the pin 155f is positioned over the lever 62 and adjacent the cam62X, so that when this lever is shifted to throw the gate for the endbars, the

ycam engages the pin and releases the tension for freer paying out ofthe thread.

When the stop motion is returned to normal position, the leverV 62 hasassumed position to form the purl stitches in the next operation buttension device 155 is engaged by the rod 173a to release the tension tofree the thread, so that when the upper thread trimming device isoperated, the blades can readily pull out and then out the thread.Closely associated with the tension device 155 is an overhanging plate156 formed with an opening 157 in Vertical alignment with the bent end130 of rod 129. In the over-r hanging portion of the plate 156 is athread guide opening 158, and'below this opening is another thread guideopening 159. 'Projecting from the side of the head is a thread guide160, and below same is a thread tension device 161 having the usualcheck-spring 162. Mounted in the free end of the bracket-arm 2 is theusual'take-up 163 formed with a thread guide opening 164. From whichlies over the upper surface of the overhanging plate having the guide158. This plate is `normally held under the bent end 130 of the rod 129by a light spring 169 on the pivot 167.

Pivoted to the upper part of the stop motion device is one end of a link170. To this link is pivoted a lever 171, the latter being reduced atone end to form'a latch 172 which cooperates with a stationary pinv 174.A lever 173 is pivot-ed to theside of the head, and its lower end ispivoted to the other end. of the link while its upper end is pivoted tothe rod 173a sharpened at its free end to engage between the discs ofthe tension device 155 to release tension on the thread at theappropriatetime in the stitching operation.

. Under the support or platform A on which the stitching mechanism ismounted, are two brackets and 181.' Supported in bearings in thebrackets 180 and 181 is a shaft 182 from which extends an arm 183.vPivoted to the arm 183 is the operating rod 184 which passes freelythrough a lug 185 on the starting lever 9. A collar 186 is adjustablyfixed on the rod 184 and between this collar and the lug 185 on thestarting lever is a spring 187, which normally tends to force the rod184 in a downward direction.A The purpose of thespring however, is toserve as a buffer when the rod starting lever 9 is operated. In otherwords, when the rod 184 is actuated up further than is necessary, thespring absorbs the excess movement and thus relieves strain on thevparts.

Pivoted to the bracket 180 is a lever 188 having oppositely disposedextensions provided with studs 189 and 190. The lower end of lever 188has a pivoted lateral lug 191 formedwith an opening for the reception ofthe end of a Z-shaped connecting bar 192. On the lower portion of theZ-shaped bar is fastened afoot pedal 193, and depending therefrom is abearing in which is mounted a grooved roller 194. The roller travels ona track 195 secured to the floor. Pivotally mounted on the bracket 180is a depending lever 196 and secured to the shaft 182 is a correspondinglever 197, the lower end of the latter and the lever 196 being pivotallyconnected together by av link 198.1k At the lower end of the lever 196is pivoted a latch lever 199 provided on its underside with acutout'portion 200 to form two abutting shoulders 201 and 202, whichcooperate with the two studsr18'9 and 190. A spring 203, attached tothe'latch lever 199 Vand the lever 188, tends to draw the stud against lthe shoulder 202 andy thus hold the; parts in normal position.

One of the purposes of this construction is to provide treadle operatingmeans whereby in the operation of the mechanism, the operator simplymoves the pedal and footforward and backward rather than-the usualtilting motion as now customarily employed.'I A further and additionalpurpose ofthe construction is to provide means to cooperate with themechanism associated with the sewing mechanism whereby to operatecertainof said mechanisms in one'movement andV perform another operationin the opposite movement. Once the machinehisv started,-

the various movements of the foot may take place,

but the operation of the mechanisms 4previously actuated cannot again beeffecteduntil the cycle of the stitching operation is over, and eventhen, operation cannot take vplace unless the' stitching has beenproperly formed.

In operation-assume the parts are in normal position, that is, aprevious operation Vhas been completed, and it is desired to remove thepiece of clothand insert another piece to formV a buttonhole.

Thei operator forces the treadle rearwardly against the tension ofspring 203, which rocks the lever 188 and places the stud 189 inengagement with the shoulder 201, and hence, the latch lever 199 ispulled rearwardly, and through the lever connections'l95, 197, 198 and183, pull is exerted 'on' the roti' 184, as shown in full lines in Fig.25. Pull lon the rod 184 rocks the starting lever 9, and roller-32 rstengages the cam 33 and rocks the lever 34. In this movement of the lever35, the bevelle'd end 36 engages the lug 37, and slides therod 31 'whichin turn partially rotates the stub shaft 26 to openvup the cutting blade28 and the thread holdingl blade 27 to pass the needle thread to aposition to engage the thread when the movement-of the blades isreversed. The'bevelled end 36 of lever 34of course swings in an arc andslips past the lug 37 as shown in fulllines in Fig. 8,V and immediatelythe spring 38 returns the cutting blade and'thread holding blade tonormal position, as shown in dotted lines in said figure. In returningto normal position, the needle thread is first engaged by the threadholding blade' 27 and `forced into the recess 25 in the presser foot andis pinched or held between the upper wall of the recess and the blade.As previously'stated, the cutting edge of the cutting 100 blade 28 isstepped back of the edge of the thread holding bladeso that when theblades enter the recess25," the threadwill iirstbe pinched andheld,'then'the cutting edge engages thev lower wall ofthe recess 25 andsevers the thread close 105 to the work but leaving a short end. Afteroperation of the blades 27 and 28,- and upon continued movement of thetreadle, the roller 10 contacts with' tail of the cloth clamp lever 7and raises the forward'end for the withdrawal of and'll the insertion ofanother piece of work in which is to be formed a buttonhole. AThe workis inserted under the presser lfoot and the operator reversesthemovement of the treadleV and 'the cloth' clamp isclosed vbythe action ofspring 20. 115 In reversingthe treadle, itis moved past the neutralposition, shownin Fig. 24, to the position shown in dotted lines in Fig.25. Obviously in reversing the movement of thetreadle, the stud 190 willengagethe shoulder 202 on the latch 120 lever l99','and'vthrough'theconnections, raise the rod 184. Raising rod184 rocks the extension 11 oflever 9, and its -end engages the roller 12 and rocks the belt shiftinglever 13 and tilts the stop motion' device'A n its'pivots 6a, andthrowsthe 125 belt from the loose tothe fast pulley. In rocking thelbelt shifting leverV 13, the link 103 is moved and the latch 102 springsback of the stop 101 tof-lock the belt shifting'leverinposition duringthe`-stitching` operation and thus prevent the 13() operator/carelesslyor inadvertently shifting the belt during `a cycle of stitching.

Intilting or setting'the stop motion device throughope'ration oflever13, the rod 16 is depressed' to permit the latchlever 117 to engage 135the not'ch17and"lock said stop motion device in operative relation.Simultaneously the link 170 is advanced and rocks'lever 173 to withdrawthe `device 173a from between the tension discs of tension device 155,whereby the latter places the 140. necessary Vtension on the threadforproper stitching. In setting the stop motion device in running position,the'shaft 131 is also rocked by the spring 1323, Fig. 1, and throws thelatch 133 over the starting lever to prevent theoperator opening the 145clamp when the `stitching mechanism is operating, or if Afor any reasonthe stop'motion should failto come back to its normal position.

In operating the startinglever 9 to throw in the stop motion device, thecushion member 138 150 1 stationary.

contacts with the end of the transverse lever 137 and positions itshooked end 139 over the rollerv 140, so that if the stitches areproperly formed and the cutting blade has operated properly, the roller140 will strike the hooked end of the lever and free the latch 136 fromthe starting lever 9. The purpose of tilting the transverse lever 137 isto position the latch 136 over the starting lever 9 and lock the same toprevent the operator raising the cloth clamp during the time thestitching mechanism is in operation or until such time as the buttonholecutting blade returns to its normal position. Y Y y Setting the stopmotion device starts the mechanism, and as shaft 5 rotates, the cam 126aon one wall of notch 126, engages the bent end of rod 125 and raises therod 128 under the arm 124 of the interponent and'at the same time rod129 is elevated and the bent end 130 is removed from the opening 157 andat the same time frees plate 168 and permits spring 169 to throw it toposition covering the hole 157 but free of drag upon the thread. -Q

The stitching mechanism is now operating and about three or fourtying-in stitches are formed to tie in the thread, then the cloth clampand usual step by step movement feed the cloth under the needle. The rstrow of purl stitches are formed, and then one of the cams 53 trips thearm 52 and the gate operating mechanism is shifted to form the first endbarring stitches, then the second row of purl stitches, and finally thegate is shifted again andthe last barring stitches are formed. As thecloth clamp 7 moves in forming the first row of purl stitches, pull isexerted on the spring 34x and the latter is tensioned. When sufficienttension in spring 34x is accumulated to overcome the tension of spring31, the bevelled end 36 of bar 34 engages the bevelled face of the lug37, and forces the rod 31 laterally in slot 31h, and lug 37 slips backof the end of bar 34 in position for a subsequent operation, as shown infull and dotted lines inFig. 8.

When'the machine was last operated, the lever 87v actuated the swingingplate v85, though the connections 89 and 90, and left the free'end ofthe lower thread pinched or held between blade.

a and the finger 76 of lever 74. At the time of forming the severaltying-in stitches, previously referred to, one of the cams 53 engagesthe cam 83 and actuates the lever 74 and finger 76 thereof releases thelower thread at or about the time the cloth clamp commences to move. Inother words while the tying-in stitches are being formed, the lowerthread is held and released by the action of the cooperating cams. Thencam 83 snaps back and resets the lever 74 and its finger 76 to cooperatewith the blade 85 at or about the completion of the stitching operation.

It might be here noted Ythat while the opposite or companion cam 53 in arevolution ofthe gear wheel actuates the thread holding plate, thelatter simply idles because at this time it is free of the lower thread.

"After the tying stitches are completed, the cloth clamp advances, andwhile the next four or ve purl stitches are being formed, the larm 40remains stationary until the shaft 21 on the clampY abuts against theshoulder 5 0. At this time, the

g end of the presser foot contacts with the bent end 42 of the arm 40and the latter and cloth clamp then move together as'further stitchesare formed. As the four or five stitches mentioned are formed, the clothis advanced while the ejector 44 remains Consequently, the beginning endof the thread held .by the thread holding blade 27 engages the notchedend 45 of the ejector, and

the latter pulls or frees it from the blade 27 and lays or bends it downon the cloth to be sewed in with the last barring stitches.

In the reverse movement of the cloth clamp, it of course carrieslwith itthe arm 40 until the plate 46 on the bifurcated end of the arm contactswith the lshaft 49, at which time the ejector 43 is stopped just inadvance of the needle, while the cloth clamp continues to move to normalposition, atA which time the last end barring stitches are formed andthe free or starting end of the needle thread laid down by the ejector43 is sewed in. Before the last barring stitches are comg pleted, thecam lever 108, Fig. 5, engages the cam end of lever 97 and disengagesthe stop 101 from the latch 102 and the spring 106 rocks the beltshifting lever 13 and the belt is thrown from the fast to the loosepulley. The mechanism from this time on runs by momentum, the purpose ofwhich is to reduce the shock and strain on the parts when the stopmotion device is finally returned to its normal position and themechanism is stopped. ToY ease the release of the latch 102 at the sametime provide a convenient way of arranging the trips on the gear wheel,the cam lever 97 is spring actuated, at the same time the pivot for thecam lever is utilized for another purpose.

At about the time the last bar stitch is formed, the pivot 109 engagesthe end of the lever 112 and releases the latch 117 from the notch 17and unlocks the stop motion device. Then the usual stop cam 400 acts onthe -usual plunger bar 132b of the stop motion device and rocks thelever 87 to actuate the cutting blade 88. At this time, the bar 128 hasbeen dropped by reason of the slot 126 having been positioned to permitthe end of bar 125 to fall, and spring 120a pulls the interponent 123 inposition to-engage the pin 121. When pin 121 israised by actuation oflever 87, the roller 140 strikes the hook-139 and removes the latch 136from the starting lever 9. Movement of the lever 87 imparts motion tothe lever 89 and link 90 andxactuates the combined thread puller andcutting blade 85a. That is to say, because of the rapid movement of thelever 87, the blade 85is first rocked in direction of arrow a-a in Fig.14 past the thread b as shown in dotted lines in said figure, so as toposition the blade in front of the thread to pull it over. Then with aquick 'snap action, the movement of the blade 85a is reversed and itdrags the thread over on the finger y76 and under the base of themachine. This results in the thread being held between the nger 76 andblade 85EL and it is simultaneously severed between the said blade 35aand the base of the machine.

At-th'e time the stop cam 400 depresses the stopmotion plunger rod13221, the cam lug 402 catches under the spring pin 403, and when therod 1322L springs upwardly, it rocks the arm 132 and tilts the latch 133and frees the starting lever 9 and the cloth clamp is free to be raised.Y

One of the fundamental features of this improvrernent is toautomatically lock the mechanismto prevent the operator disturbing theoperation of the machine in a cycle of movement and thus preventbreaking the parts and Vruining the work. Several of these lockingfeatures are controlled entirely by the thread, so that if .in a givencycle of operation anythingihappens which produces improper stitches, orthe thread should break, or the cutting blade should stick or otherwisenot come back to its normal position, the operator Vment with thestarting lever 9.

cannot lift the work clamp. Hence, in case `of skipped, loose, orimproper stitches, or if the cutting blade sticks, the work remainsunder the work clamp and the operator cannot remove it until the threadis repaired or other imperfections vare cured and the locks reset. Thenthe machine can be again started and the previously stitched buttonholeis worked over again, and the work is saved. Therefore, the variouslocking devices assume importance.

Let it be assumed the tension of the thread becomes so loose as to formimproper stitches, the thin resilientplate 168 has not been moved by thedrag of the thread from its position over the opening 157 at the timethe stop motion device is thrown to normal stopping position at the endof the cycle of movement. While the mechanism is stopped, the rod 129 isheld suspended by the plate 168 and the bar 128 remains under the arm124 of the interponent 123 and prevents the upper notched end of thelatter being positioned under the pin 121. Thus when bar 87 is operated,it merely raised the interponent without operating the bar 122 to tripthe cutting blade 88. As the notched endV of the interponentcannotengage the pin 121, the position of the transverse bar 137 is notdisturbed, hence the latch 136 remains in engagement with the startinglever and cannot be actuated by the operator, and therefore the clamp vcannot be raised. The thread is repaired or the desired adjustment ismade, then without releasing the latch 136, the operator can operate thetreadle and start the stitching mechanism and the saine piece of clothcan be worked over again in A identically the same place.

It very frequently happens that the cutting blade 88 sticks and fails tocome back to normal position. When this occurs, the operator in the rushto insert another piece of work actuates thetreadle, and as the cuttingblade is in the path of the clamp and other parts, the blade is bent orbroken and undue strain is put on the mechanism.

To prevent this occurring, means are provided to prevent the operatorstarting the mechanism if the cutter should stick, although the treadleis free to be moved idly. When the bar 87 is actuated by the stop motiondevice to drive the cutting blade down to cut the slit in the cloth, itrocks the lever 171 and brings thelatch end 172 up adjacent the pinv174. Now if the cutting A' blade 88 should stick, bar 87 will not comeback to its normal position, hence the shoulder of latch end 172 of thelever is positioned in front of the pin 174, and any attempt to tilt thestop motion device to running position results in the shouldercontacting with the pin and thus forming a lock. As the arm 132 cannotreturn to its normal position until the bar 87 assumes its normalposition, it follows shaft 131 will not be disturbed, hence the latch133 remains in engage- Therefore, should the operator attempt to openthe clamp to remove the Work Without having noticed that the cuttingblade was stuck, she .will only be able to idly actuate the treadle,then she is apprised something is Wrong. If the operator attempts tomove the treadle to start the stitching mechanism without noting thatthe cutting blade is stuck, it cannot be donc, because of the positionof the'shoulder of the latch end 172 of the bar 171 being in position toengage the pin 174. Any attempt to start the mechanism under theconditions noted, it will be obvious at once that the latch bar 171prevents tilting of the stop motion jdevice to'running position, anduntil the cutting blade 88 is returned or adjusted so that it assumesnormal position, the latches 172 and 133 and the stop motion devicecannot assume vtheir normal positions. Even though in the partialoperation of the cutting blade the transverse lever 137 is tripped andthe latch 136 released, it follows that latch 133 prevents the startinglever being operated to open the clamp.

If the operator has any doubt as to the slit in the buttonhole havingbeen correctly formed, and desires to re-work it, the slit-cutting bladeis adjusted, the latches and stop motion device are reset, and withoutlifting the clamp, the cloth is in identically the same place and can bereworked with assurance that the buttonhole has been properly formed.

' It is of importance in a machine of this type that the thread beproperly measured to supply the desired length of thread. Theimprovements make ample provision to meet this contingency as Will beevident from the following description.

During the stitching operation, the shaft 141 is oscillated, and in onedirection of movement, the guide 145 exerts a pull on the thread aboutsufficient to draw off a length of thread to form a stitch, While at thesame time, the lug 146 moves down and restores the tension on the threadpassing around the tension device 150. In

y the reverse movement of the shaft 141, the guide 145 slackens thethread, while the lug 146, acting on the bent end 147 of the plate,releases the tension'and permits of the slack thread pulled olf by theguide 145 to be readily fed in the stitching operation. The tensiondevice 155 retains a normal tension on the thread from the iirst tensiondevice 152, except at the time the barring stitches are formed, and atthe same time tensions the thread properly for the thread feed. That is,as the stitches are formed, pull is exerted on the thread, and as thelatter passes over the plate 156, the thread is frictionally draggedstep by step under the thin spring plate 168 until the required numberof stitches have been produced in the making of a buttonhole. When thebuttonhole stitches are completed, the bent end 130 of the rod 129 dropsin the opening 157 in the plate which drops rods 128 and 126, aspreviously described. When the end 130 of the rod drops, it holds thethin plate 168 against the tension of its spring until the nextstitching operation is started.

What is claimed is:

1. In combination, a buttonhole machine including stitching mechanism, acloth clamp, cloth clamp raising means, a stop motion device, treadle Ldirection and to actuate the stop motion device when said treadle ismoved in the opposite direction.

2. In combination, a buttonhole machine including stitching mechanism, acloth clamp, cloth clamp raising means, a stop motion device, threadtensioning means, a latch under control of the thread tensioning meansto lock the cloth clamp raising means when the stitching mechanism is inoperation, a second latch under control of the stop motion device tolock the cloth clamp raising means during the stitching operation,treadle operating mechanism comprising a system of levers and a treadle,a straight track on which the treadle slides, whereby to actuate thecloth clamp raising means when said treadle is moved in one direction,and to actuate the stop motion device when said treadle is moved in theopposite direction, the latches being arranged to prevent raising of theclamp if the `stitches are improperly formed or the stop motion fails toreturn to normal position and means between the treadle mechanism andthe cloth clamp raising means to permit movement of said mechanismwithout actuating the clamp or the stop motion device,

3. In combination, a machine of the buttonhole sewing typehavingstitch-forming mechanism, a cloth-clamp, a stop-motion device,control means mounted on said machine and operable in one direction toraise the cloth-clamp and in they opposite direction to set thestop-motion device to start the sewing operation, a platform on whichthe machine is stationed for use, manually operated means mounted belowsaidplatform and movable in opposite directions from a neutral position,and a rod and spring connecting said manually operated means and saidcontrol means to operate said control means to raise the work-clamp whensaid manually operated means is moved in one direction and to yieldinglyoperate said control means to start the sewing operation when movedv inthe opposite direction.

4. In combination, a machine of the buttonhole sewing type havingstitch-forming mechanism, a cloth-clamp, a stop-motion device, controlmeans mountedon said machine and operable in one direction to raise thecloth-clamp and in the opposite direction to set the stop-motion deviceto start the sewing operation, a platform on which the machine isstationed for use, manually operated means mounted below said platformand movable in opposite directions from a neutral position, a rod andspring connecting said manually operated means and said control means tooperate said control means to raise the work-clamp when said manuallyoperated means is moved in one direction and to yieldingly operate saidcontrol means to start the sewing operation whenmoved in the oppositedirection, and a latch on the machine for preventing the setting of thestop-motion device to start a new sewing operation if the stop-motiondevice fails to come back to normal position at the termination of apreceding sewing operation.

5. In manually operated mechanism for lifting the work-clamp and settingthe stop-motion device of a machine of the buttonhole sewing type, thecombination with a vertically movable rod connected to the machine, of abell-crank mechanism for moving said rod', a horizontally movable barpivotally connected at one end to said bell-crank mechanism and formedwith spaced opposed shoulders, and a manually operated pivoted leverhaving spaced projections adapted to alternately engage said shoulders.

ELIZABETH R. MILLER, THOMAS F. MORRIS, JR., Executors ofthe Estate ofHenry C. Miller, De-

ceased.

